1. Technical Field
The present invention relates to an apparatus for applying a material to an object, a method of applying a material to an object and a display manufacturing apparatus, in particular, to an apparatus to apply a material such as a sealant to an object, a method of applying a material such as a sealant to an object and a display manufacturing device for manufacturing a display such as an electro luminescent display.
2. Description of the Related Art
A display having a light emitting element such as an organic electro luminescent (EL) device has been developed as a new display, as a replacement for liquid crystal displays.
However, absorption of water shortens a lifetime of the light emitting element. In order to avoid such absorption, a display having an organic electro luminescent device between a glass substrate and a sealing glass is surrounded by a sealant to seal the device. The sealant keeps the device from absorption of moisture contained in air.
Further, it is necessary to fill a working space where an EL display is manufactured with inert gas to avoid water absorption when manufacturing an organic EL display. Therefore, a working space under limited water content (under dew point control) where an EL device can be kept from water absorption is formed. Forming such a working space is shown in Japanese Patent Publication No. 2002-216958.
When sealing an EL device, a sealing glass is bonded with a glass substrate on which an EL device is set after applying a sealant on the sealing glass. It is not necessary to apply a sealant on the sealing glass under dew point control because an EL device is set not on the sealing glass but on the glass substrate. In other words, no applying apparatus applies a sealant under dew point control.
However, not having such an applying apparatus limits flexibility in optimizing a procedure for manufacturing an EL display.
Further, it is necessary for a working space of a bonding apparatus to control a dew point in order for an EL device not to be exposed in air when bonding the sealing glass with the glass substrate on which an EL device is set. Therefore, an anterior chamber to carry in the sealing glass is provided in order to form an “air lock” and maintain the working space under dew point control.
However, providing an anterior chamber causes a longer tact time and a lowered productivity, because it is necessary to fill the anterior chamber with inert gas every time the sealing glass is carried in. Consequently, shorting a tact time is desired.